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afløses af en fin. ophcfiet Linie. Denne Fure ligesom
dækkes af dens venstre fremragende, temmelig skarpe Kand,
der taber sig i den ovenomtalte fine, öphøiedc Linie.
Cellerne ere stillede paa hver Side af Midtfuren i
langt trå hinanden staaende Rækker, Fig. 9. 11. Disse
have en meget skraat opadgaaende Retning fra Dorsal- til
Ventralfladen. I hver Række er der 3 Celler, som have
en Traktforin og ere fra. 3—5""" lange, saaledes nemlig at
den egentlige Dorsalcelle er mindst, og den, der staar
nærmest Ventralfladen, er størst, Fig. 10. Cellerne ere glatte,
glindsende. deres indre Væg er fastvoxet til Rachis og er
noget længere end den ydre, Fig. 10, a, hvoraf følger, at
Aahningen er skjæv saaledes, at den ydre, fri Rand, der i
Regelen er forsynet meel 3 stærke Tænder, staar lavere end
den indre, fastvoxede Rand, Fig. 10. b.
Celleaabningen er 1,5""" vid, og paa enkelte Celler
eider paa den fri Rand 5—(5 meget smaa Papiller, der giver
Randen et undulerende Udseende. Paa den nederste Del
af Rachis ere Cellerne mindre, staa længere Ira hinanden
og tildels kun 2 i hver Række, imedens paa den øverste
Del af Rachis staa Cellerne noget tættere, og her sees
enkelte mindre Celler, som staa til Siden af Rækken uden
egentlig at tilhøre denne. Fig. 8.
Imellem liver Cellerække er en Gruppe Zooider, der
strække sig fra Dorsalttadens Midtfure paa liver Side til
henimod Ventralfladen, hvor de ordne sig i Rækker (2—3
i hver), Fig. 8. It», c. imedens de langs Midtfuren danne
en uregelmæssig Længderække, Fig. 9. Lignende Zooider
tindes ogsaa dels imellem Cellerne, hvor de staa enkeltvis,
dels paa selve Cellen, Fig. 10, e.
Nedenfor de udviklede. Celler sees mange, næsten
paa-tversgaaende Rækker med uudviklede Celler, 2—3 i hver
Række, og imellem hvilke tindes enkeltstaaende Zooider.
Ventralfladen er lidt hvælvet og har langs Midten en
cylindrisk, stærkt fremspringende, vandklar. nøgen Kjøl,
der ser ud, som om det var en fin Glasstav, der var
placeret langs denne Flades Midtlinie, Fig. 10, /’. Paa hver
Side al’ Kjolen iagttages to Længderækker Zooider, Fig.
10, ff, der ere noget mere eleverede end di* paa
Dorsalfladen.
Cellerne ere rigt besatte med større og mindre
stav-formige, trekantede Spikier, der ere vandklare, — kun
yderst faa have et rødligt Skjær, som imidlertid er saa
svagt, at det kun med stor Opmærksomhed kan iagttages.
Spiklerne ere fta0,222"’"’ 1,023""" lange og fra0,041 —0,055"""
brede og ere ordnede saaledes, at i Midtpartiet af Cellen
ligge de næsten i en ret Linie, men til Siderne straale de
vifteformigt ud fra Midtlinien, hvorved de i den nederste
Knile af Cellen samle sig i en afstumpet Konus, imedens
de foroven pyramideformigt gaa over i Tænderne. I Re-
furrow gradually disappears, and h replaced by a slender
elevated line. This furrow is covered, as it were, by its
protuberant, rather sharp left margin, which becomes
absorbed in the slender elevated line, spoken ol’ above.
The cells are situated on each side of the mesial
furrow, in series, placed at considerable intervals apart
(figs. 9, 11). These have a verv diagonal, upward direction,
from the dorsal to the ventral surface. In each series,
there are 3 cells, having a funnel-shape, and measuring
from 3—5""" in length; they are so placed that, the
real dorsal cell is the smallest one, and tin* cell which is
placed nearest to the ventral sun ace is the largest one
(fig. 10). The cells are smooth, and shining; the inner
wall is concreted with the rachis, and is somewhat
longer than the outer wall (tig. 10. a), and consequently,
(lie aperture becomes crooked, in such manner, that the
exterior free margin; which is usually furnished with 3
strong teeth; is situated lower than the inner concreted
margin (fig. 10. b).
The cellular aperture is 1.5""" wide: and. in a few
cells, there are found 5—(5 very small papillæ situated
on the free margin, which impart to it an undulatory
appearance. On the inferior part of the rachis. the cells
are smaller, and are placed further apart from each other:
and, occasionally, there are only 2 in each series; whilst,
upon the superior part of the rachis. the cells are placed
somewhat closer; in this situation, a few smaller cells
are seen placed at the side of the series, without, actually,
belonging to it (fig. 8).
Between each cellular series, there is a group of
zooids, extending on each side, from the mesial furrow on
the dorsal surface to the proximity of the ventral surface,
where, they arrange themselves in series (2 ."> in each)
(fig. 8, 10, c), whilst, along the mesial furrow, they form
an irregular longitudinal series (fig. 9). Similar zooids are
found, also, partly, between the cells, where, they appear,
singly, and partly, on the cell itself (fig. 10, e).
Below the developed cells, ’many almost transversal
series of undeveloped cells (2—3 in each series) are
observed. and between these, solitary zooids are found.
The ventral surface is somewhat arched, and has.
along its middle, a cylindrical, strongly protuberant bare
keel, which is clear as water, and appears as if. it was a
slender glass-rod placed along [the mesial line of this surface
(fig. 10. /’). On each side of this keel, two longitudinal
series of zooids are observed (fig. 10, ff); these are
somewhat more elevated than those of the dorsal surface.
The cells are richly beset with, larger and smaller,
rod-like, triangular spicules, which are clear as water;
but an extreme few have a reddish tinge, which however,
is so faint, that it can only be observed on very close
attention being paid to it. The spicules measure from
0.222"""—1.023""" in length, and from 0.041—0..055""" in
breadth; and they are arranged in such manner, that in
the mesial part ol’ the cell, they are found placed, almost,
in a straight line, whilst, on the sides, they radiate from
the mesial line in fan-shape, and they, thus, collect together
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